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Acta Cryst. (2014). A70, C948
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Fischer-Tropsch (FT) synthesis is an important process to manufacture hydrocarbons and oxygenated hydrocarbons from mixtures of carbon monoxide and hydrogen (syngas). The catalysis process occurs on for example cobalt metal surfaces at elevated temperatures and pressures. A fundamental understanding of the reduction pathway of supported cobalt oxides, and the intermediate species present during the activation, can assist in developing improved industrial supported cobalt catalysts. Measurements were done during in-situ hydrogen activation of a model Co/alumina catalyst using in-situ synchrotron X-ray powder diffraction and pair-distribution function (PDF) analysis. Strong metal-support interactions between the Co and the support1 can make the catalyst more stable towards sintering. The supported cobalt oxide catalyst precursors have to undergo reductive pre-treatments before their use as FT catalysts. During activation the cobalt oxides evolve, resulting in the formation of metallic cobalt depending on temperature, pressure of activation gases, concentration, time of exposure etc. The effect of hydrogen activation treatments on model catalysts were reported previously [1,2], however analysis of the alumina support phases was excluded from the interpretation by subtraction and normalisation. The PDF refinement accounted for all cobalt present in the catalyst sample and after reduction mainly Co(fcc) with a little Co(hcp) was found to be present. This is a novel approach to in situ PDF analysis of catalysts containing a mixture of phases [3].
Keywords: in situ XRD; PDF; catalyst.

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Acta Cryst. (2014). A70, C1561
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This work reports on the synthesis, crystal structural determination, conformational analysis and antiproliferative activity of an alkylsulfonamide analogue of capsaicin – RPF151 (N-(benzo[d][1,3]dioxol-5-ylmethyl)butane-1-sulfonamide). Capsaicin is the primary pungent and irritating natural product present in a variety of red chilli peppers of the genus Capsicum, and was reported to selectively inhibit the growth and to induce apoptosis in a wide variety of tumour cell lines.1-3 RPF151 was obtained by a simple reaction of 1-butanesulfonyl chloride with piperonylamine, in an anhydrous DCM (dichloromethane) and TEA (tetraethylammonium) mixture (Yield 70%). The crystal structure determination was carried out by means of an ab initio simulated annealing approach using X-ray powder diffraction data. RPF151 crystallized under a monoclinic system (P21/a) with final unit cell parameters refined using the Rietveld method: a = 29.0171(13) Å, b = 10.4745(3) Å, c = 9.1117(3) Å, β = 104.268(4)0, V = 2683.98(17) Å3, Z = 8, Z' = 2. The statistical parameter as well as R-factors were: χ2 = 1.11, Rwp = 0046, Rexp = 0.042 and RBragg = 0.010. The molecules are held together along the c-axis by hydrogen bonds involving the atoms N(37)–H(42)···O(4). Calculated elemental analysis for C12H17NO4S (271.09 g mol-1) shows C = 53.12, H = 6.32 and N = 5.16 while experimental values are C = 53.13, H = 6.39 and N = 5.14. The effects of RPF151 10 μM on human umbilical vein endothelial cells (HUVEC) proliferation was tested by flow cytometry. It was verified that RPF151 induced changes on cell morphology, a fact corroborated by HUVEC cell size and complexity. Furthermore, it caused a significant reduction on cell proliferation and evidenced no cytotoxic effects. Therefore, RPF151 could be developed as a candidate to an anti-angiogenic drug for the fighting against cancer. Acknowledgments: We are grateful to FAPESP (proc. nr.: 2013/18160-4, 2012/23233-8 and 2008/10537-3), CNPq (proc. nr. 305186/2012-4 and 477296/2011-4) and Provost's Office for Research of the University of São Paulo for financial support.
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